How To Write A Business Letter For Someone Else . When you send the email, put the original recipient in the “to” field and include the additional person in the “cc” field. Write the letter you want to send to the primary recipient and another person. How To Sign A Letter On Behalf Of Someone Else Example from kadakawa.org Also depending on the content or intent of the letter, you may want to ask hr or some other authority about the proper “chain of command” and protocol for your work. Most content is left justified in this style, just as in the block format letter. Start with the salutation, “dear” followed by the person’s name, title and a comma.